CH4 + 2 Cl2--> CH2Cl2 + 2HCl
Cl-Cl bond energy: 242 kj/mole
1. Calculate the amount of energy (Joules) needed to break a single Cl-Cl bond.
2. Calculate the longest wavelength of light (meters)that can supply the energy per photon necessary to break the Cl-Cl bond.
242 kJ/mol = 242,000 J/mol
242,000 J/mol x (1 mol/6.022 x 10^23 molecules) = E for one molecule in joules.
E = hc/wavelength.
Calculate the total energy required to break bonds of the reactants if c-h is 414 kj mol
O-h 460 kj mol
o=o 499
c=o 799 kj mol
Ch4+2h2o ›2h2oo+co2+energy c-h 414 kj mol
o-h 460 kj mol
o=o 499 kj mol
c=h 799 kj mol
To calculate the amount of energy needed to break a single Cl-Cl bond, we can use the given bond energy of 242 kJ/mole and convert it to kJ per bond.
1. To calculate the energy needed to break a single Cl-Cl bond in kJ, we divide the bond energy by the number of bonds broken:
Energy per Cl-Cl bond = 242 kJ / 2 = 121 kJ.
However, to answer the question, we need to convert the energy from kJ to Joules since 1 kJ equals 1000 Joules.
1. The energy needed to break a single Cl-Cl bond is therefore:
Energy per Cl-Cl bond = 121 kJ * 1000 = 121,000 J.
Now, let's proceed to the second question.
2. To calculate the longest wavelength of light that can supply the energy per photon necessary to break the Cl-Cl bond, we need to find the number of photons that can provide the required energy.
The energy per photon (E) is given by Planck's equation, which relates energy to frequency:
E = h * f
Where:
E = Energy per photon
h = Planck's constant (6.626 x 10^-34 J s)
f = frequency of light
The energy per photon required to break the Cl-Cl bond is 121,000 J, as calculated in the first question.
To find the frequency of light required, we rearrange the equation as follows:
f = E / h
Since the speed of light (c) is related to the wavelength (λ) and frequency (f) of light according to the equation c = λ * f (where c is approximately equal to 3 x 10^8 m/s), we can substitute f with c / λ to get:
λ = c / f
Since we want to find the longest wavelength, we need to find the smallest frequency that satisfies the equation.
Plugging in the values:
λ = c / (E / h)
Substituting the known values:
λ = (3 x 10^8 m/s) / (121,000 J / (6.626 x 10^-34 J s))
Calculating:
λ = (3 x 10^8 m/s) * (6.626 x 10^-34 J s) / 121,000 J
λ = 1.63 x 10^-6 m
Therefore, the longest wavelength of light (in meters) that can supply the energy per photon necessary to break the Cl-Cl bond is approximately 1.63 x 10^-6 meters.